title: Synthesis and characterization of poly(dimethylsiloxane)-poly(ethylene oxide)-heparin CBABC type block copolymers.
abstract: Heparin and poly(ethylene oxide) were coupled to a central anchoring block of poly(dimethylsiloxane) in order to investigate its blood compatible properties. Diamino telechelic poly(dimethylsiloxane) (PDMS-(NH2)2, Mw = 20,000) was first modified to isocyanate functionalities using toluene 2,4-diisocyanate. This modified PDMS was then coupled to diamino-telechelic poly(ethylene oxide) (PEO-(NH2)2, Mw = 2000, 4000, 6000) to create BAB type copolymers having terminal free amino groups. These amino groups were covalently coupled to heparin containing terminal aldehyde groups using sodium cyanoborohydride to yield a bioactive, CBABC type block copolymer. The physical characterization of these copolymers was performed with IR, NMR, sulphur elemental analysis, Wilhelmy plate contact angle, and differential scanning calorimetry (DSC). CBABC block copolymer surfaces demonstrated heparin bioactivity in in vitro evaluation, and improved nonthrombogenic properties during ex vivo A-A shunt experiments.
authors.affiliation: Department of Pharmaceutics, University of Utah, Salt Lake 84112.
authors.forename: A Z
authors.initials: AZ
authors.lastname: Piao
authors.forename: C
authors.initials: C
authors.lastname: Nojiri
authors.forename: K D
authors.initials: KD
authors.lastname: Park
authors.forename: H
authors.initials: H
authors.lastname: Jacobs
authors.forename: J
authors.initials: J
authors.lastname: Feijen
authors.forename: S W
authors.initials: SW
authors.lastname: Kim
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004129:Dimethylpolysiloxanes; D006493:Heparin / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D008297:Male; D015394:Molecular Structure; D008970:Molecular Weight; D010973:Platelet Adhesiveness / Q000187:drug effects; D011817:Rabbits; D012833:Siloxanes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D013918:Thrombin Time; D014048:Tolonium Chloride
chemical_list: D001672:Biocompatible Materials; D004129:Dimethylpolysiloxanes; D012833:Siloxanes; C055740:poly(dimethylsiloxane)-(polyethylene oxide)-heparin copolymer; D014048:Tolonium Chloride; D006493:Heparin